Automatic reclosing circuit breaker system



AUTOMATIC RECLOSING CIRCUIT BREAKER SYSTEM Filed Nov. 15, 1940WlTNESSESr- 7 INVENTOR M Mrnarzia/kyajyzg.

Patented Mar. 9, 1943 UNITED STATES PATENT OFFICE AUTOMATIO RECLOSINGCIRCUIT BREAKER SYSTEM Application November 15, 1940, Serial No. 365,825In Germany October 6, 1939 19 Claims. (01. 175-294) This inventionrelates to circuit interrupters and, more particularly, to high capacitycircuit interrupters for use in electrical transmission or distributionsystems.

It is a known practice to use in high-voltage circuits certain switchingarrangements for the purpose of suppressing any fault-condition thatdevelops in such a circuit in the form of an arc in air or flash-over.Such switching arrangements, which are not designed to remainpermanently in the oil position, function by temporarily interruptingthe flow of power towards the point at which such a fault-condition hasdeveloped. These switching arrangements called short-circuitsuppressors, reclose almost immediately after having interrupted thecircuit. One type of such short circuit suppressor is equipped with acircuit interrupter for interrupting the circuit and with a switch inparallel with the interrupter for reclosing the circuit. In otherdesigns, however, the same interrupter that is being used forinterrupting the circuit may be employed for the reclosure. Forinstance, in the case of an interrupter in which the arc is interruptedwith the aid of compressed gas, it is feasible to withdraw the movablerod-shaped contact member only up to the point at which this member isin the most favorable position for extinguishing the are, although forthis particular position of the movable contact member the distancebetween this member and the stationary contact member would not be largeenough if the interruption had to be of a permanent nature. And whenbreakers operating with a nonconductive liquid in the switching chamberare used for suppressing short-circuits, the disconnecting switches withcontacts in air that are usually connected in series with'such breakersmay be omitted; Switching arrangements of the kind to whichreference isbeing made are not, as a rule, capable of use as a disconnecting deviceto permanently interrupt the circuit since they are not constructed toprovide a large enough gap in the open position for this purpose.

Under certain instances, however, switching arrangements of the kind towhich reference is being made, in addition to being employed asshort-circuit suppressors, have to function occasionally as tie-breakersor as transformer breakers. In such an instance it is advisable toprovide breaker arrangements that can be used equally well asdisconnecting devices, that is, as devices for permanently interruptingthe circuit in which they are employed.

In order to meet the latter requirement with rather simple means thatwill nevertheless be sufiiciently reliable under operating conditions,the present invention has for an object the provision of a switchingarrangement in which the disconnecting switch normally provided inseries with the device constituting the short-circuit suppressor isequipped with a remotely controlable operating mechanism which, togetherwith the operating mechanism for the short-circuit suppressor, is socontrolled that the closing as well as the opening motion of thedisconnecting switch will be caused to take place exactly within theinterval of time during which the highvoltage circuit is temporarilyinterrupted by the short-circuit suppressor.

Another object of this invention is to provide a circuit interrupterhaving a disconnecting switch which is operable to permanently interruptthe circuit during the time interval when the circuit is momentarilyinterrupted by the circuit interrupter.

Another object of the invention is the provision of switching apparatuscomprising a circuit interrupting device which is automatically operableto interrupt and automatically reclose the circuit, and a disconnectingswitch in series therewith to provide for normal opening and closing ofthe circuit, the operating means of the switch being interlocked withthe interrupting device in such a way that the circuit is alwaysinterrupted and open at the interrupting device when the switch isoperated.

Another object of the invention is the provision of switching apparatuscomprising an automatic reclosing circuit interrupting device, adisconnecting switch in series therewith, and operating means operableto open or close the disconnecting switch and to cause the circuit to betemporarily interrupted by the interrupting device whenever thedisconnecting switch is operated.

Another object of the invention is to provide a circuit interrupterhaving an improved operating mechanism which insures complete openingand closing movements of the interrupter.

Another object of the invention is to provide a circuit interrupter orswitch having a compressed air operating mechanism with auxiliary airreservoirs for collecting sufiicient air under pressure to insure a fullstroke if the supply of operating air should be prematurely interrupted.

Another object of the invention is to provide switching apparatus havinga plurality of switching devices with a control system which preventsoperation of one of said switch devices to open or closed position, whenany one of the remainder of the switch devices is in the closedposition.

Another object of the invention is to provide a circuit breaker havingan interrupting switch, a reclosing switch, and a disconnecting switchwith means controlled by the interrupting switch and by the reclosingswitch to suppress movement of the disconnecting switch to open positionor to closed position until both the interrupting switch and thereclosing switch are open.

The novel features that are considered characteristic of the inventionare set forth in particular in the appended claims. The inventionitself, however, both as to structure and operation, together withadditional objects and advantages thereof, will be best understood fromthe following detailed description of one embodiment thereof when readin conjunction with the accompanying drawing, which diagrammaticallyillustrates switching apparatus embodying the principles of theinvention.

Referring to the drawing, indicates a circuit interrupting switch and 2indicates a circuit closing switch connected in a high capacity circuitin parallel with the interrupting switch I. A disconnecting switch 3 isconnected in the circuit in series with the switches I and 2. Theinterrupting switch I is biased in a clockwise or circuit openingdirection by a spring having one end connected to an arm I movable withthe switch I, and the other end suitably connected to a stationary partof the circuit interrupter. A spring 9 having one end connected to anarm I'I movable with the circuit closing switch 2' and the other endconnected to a stationary part biases the closing switch 2 in aclockwise or circuit closing direction. A latch I3 cooperates with alatch member I5 movable with a guided rod I! to releasably restrain theswitch member I in closed position, and a guided rod l3 movable with theswitch I cooperates with the switch member 2 to restrain the switch 2 inopen circuit position when the switch I is in closed position.

A trip device 2I comprising a trip coil 23 and a cooperating movablecore 25 is provided to release the rod l1 and permit the springs 5 and9, respectively, to open the interrupting switch I and close thereclosing switch 2.

The interrupting switch I is operated to its closed position, and thereclosing switch 2 i operated to its open position by means of acompressed air device 21 comprising a cylinder 29 and a piston 35reciprocably movable therein, and which is operatively connected to theoperating rod IT. Air or other suitable fluid under pressure admitted tothe cylinder under the control of an electro-magnetically operatedcontrol valve 33. The control valve 33 is connected to a suitable sourceof compressed fluid by a pipe 35, and a pipe 3? conveys the fluid fromthe valve to the cylinder.

The control valve 33 comprises a U-shapet magnet core 39 having one legsecured to the valve casing 4! and having a winding 43 on the other leg.When the coil 43 is energized, in a manner to be described later, itattracts an armature 35 pivotally mounted on the casing GI and thearmature l5 actuates a pilot valve met ber 51 to operate a main valveand thereby admit compressed air through the pipe 3? to the cylinder 29.

The disconnecting switch 3 is operated to its open position and also toits closed position by means of an air pressure operated device .9. Thisdevice comprises a cylinder 5I within which a piston 53 is reciprocablymovable. An operating rod 55 connects the piston 53 to the disconnectingswitch member 3. Provision is made to selectively admit compressed airinto the cylinder to the left and to the right of the piston 53 in orderto open and close the disconnecting switch 3. Two valves 51 and 59 areprovided for this purpose and are adapted to be operated byelectro-magnets comprising windings 6| and 63 which, when energized,attract their respective armatures 65 and 61 to operate the valves 51and 59.

The interrupter switch I is opened and the reclosing switch 2 is closedsubstantially instantaneously thereafter in response to a faultcondition such as an are short circuit or flashover in the circuit,through the agency of the contacts I5 of a conventional fault relay.When the relay contacts !5 close a circuit is established for energizingthe coil 23 of the trip device 2|. The circuit may be traced from asource conductor ll of an auxiliary supply line through a conductor I9,the relay contacts i5, conductors SI and 83, auxiliary contacts closedwhen the interrupting switch I is closed, conductor 81, coil 23 of thetrip device 2|, conductors 9!, and 93 to a source conductor 95.Energization of the trip coil 23 operates the latch E3 to release theoperating rod I1, whereupon the spring 5 moves the interrupting switch Ito open position and the spring 9 moves the reclosing switch 2 to itsclosed position thereby immediately reclosing the main circuit.

The majority of faults occurring on the transmission line are of atransitory nature and will have disappeared in the brief interval oftime between the opening of the switch I and the closing of the switch2, and these switches may then be reset to their normal positions, asshown. The switch I is closed and the switch 2 is opened by thecompressed air device 27. It was previously stated that air underpressure is admitted to the cylinder 29 by operation of the controlvalve 33 upon energization of the winding 43.

- This is effected by manual operation of a resetting switch in.Operation of the switch 91 closes contacts 93, which establishes acircuit through the coil 43 extending from the conductor 'I'I, throughconductors F9 and NH, contacts 99, conductor I53, coil 43, and conductor93 to the conductor 95.

Operation of the valve 41 admits air to the cylinder 23 which causes thepiston 3I to move to the left, opening the switch 2 and closing switchI. When the rod I1 is moved toward the left to effect closing of theswitch I, the latch l3 resumes its latching position. The movement ofthe switch member I to closed position is transmitted by the rod I9 toopen the switch 2.

It was stated previously that the disconnecting switch 3 is both openedand closed by means of the device 49, under control of theelectro-magnetically operated valves 5! and 59. These valves areoperated under the control of a manually operable switch indicatedgenerally by the reference numeral I05. Manipulation of the switch I05also elfects opening of the interrupting switch I.

The switch I85 comprises three switch blades ill", I 09, and II 1operatively connected by means of a tie rod H3, and each electricallyconnected to the conductor NH. The switch blades I09, III and H3 areprovided with an operating handle H4 and are operable in both directionsas a unit, and each is adapted to cooperate with two contacts,respectively, H5 and H1, H9 and I2I, and I23 and I25.

When it is desired to open the disconnecting switch 3, the handle H4 ismoved toward the right, moving the switch blades I01, I09 and III towardthe left into engagement with contacts H5, H9 and I23, respectively.

Since one of the important features of the invention is to open thedisconnecting switch 3 only when both the closing switch 2 and theinterrupting switch I are open, it is necessary to prevent switch 2 fromclosing when the trip device 2| is energized. This is effected byenergization of a lookout coil I21 comprising a winding I29 and amovable armature |3| adapted, when the winding I29 is energized, toengage a latch member I33 on the end of a rod I35 to prevent closing ofthe switch member 2.

Operation of the switch I05 to the off position establishes threecircuits. The first energizes the lockout coil I21 to prevent closing ofthe switch 2; the second energizes the trip device 2| to efiect openingof the interrupting switch I; and the third prepares a circuit for thecoil to efi'ect opening of the disconnecting switch 3 after switch Ireaches open position.

The first mentioned circuit is traceable from the conductor 11 throughconductors 19 and MI, the switch blade I01, contact IE5, a conductorI31, coil I29 of the lockout device I21, conductors 89, 9| and 93 to theconductor 95. Energization of the coil I29 engages the armature I3I withthe latch I33 and prevents closing of the switch 2.

The second previously mentioned circuit is established by engagement ofthe switch blade I09 with the contact M9 to energize the trip coil 23and cause opening of the interrupter switch I. This circuit is traceablefrom the conductor 11 through conductors 19 and NH, the switch bladeI09, contact I I9, a conductor |4|, the conductors BI and 83, auxiliarycontacts 85, conductor 81, coil 23 of the trip device 2|, conductors 89,9| and 93 to the conductor 95.

Energization of the trip magnet causes release of the rod I1 and thespring 5 immediately moves the switch I to open position. We now havethe switch 2 restrained in open position and the switch I in openposition.

The third previously mentioned circuit extends from the conductor 11,through conductors 19 and IOI, switch blade III, contact I23, aconductor I43, c-oil 6|, conductor I45, auxiliary contacts I41, closedwhen the switch 2 is open, a conductor I49, auxiliary contacts l5|closed when the switch I is open, conductors 9| and 93 to the conductor95.

The circuit just described energizes the coil 6| which operates thevalve 51, admitting compressed air to the left of the piston 53 andcausing opening of the switch 3. As the rod 55 moves to open the switch3, a sliding contact member I53 holds the lookout coil I29 energizeduntil the switch 3 is completely opened, whereupon the contact I53 opensdeenergizing the coil I29 which permits the switch 2 to close. Theholding circuit for the lookout device I21 extends from the conductor 11through a conductor I54, the contacts I53, a conductor I50, coil I29,conductors 39, 9| and 93 to the conductor 95.

The sliding contact I53 insures that the switch 2 will be held open, inthe event the control switch I05 is prematurely released, until thedisconnecting switch 3 is fully opened. When the disconnecting switchreaches its open position, the manual control switch I95 may then bereturned to its neutral position. The locking device |21 is thereupondeenergized, and switch 2 is moved to closed position by spring 9.

The interrupting switch I and the reclosing switch 2 may now be reset tothe normal position shown by operation of the switch 91 in the previously described manner, the disconnecting switch 3 remaining open.

With the switches in this condition, that is, the switch I closed,switch 2 open, and switch 3 open, it is necessary, in order to close thedisconnecting switch 3 against an open circuit to first open the switchI.

This is effected by operating the switch I05 to the on position toengage the switch blades I01, I99, and I I I, respectively, with thecontacts II1, |2| and I25. This operation of the switch I05 sets up thepreviously described circuit to energize the lookout relay I21 and alsocompletes the previously described circuit to energize the trip device 2I. This results in holding the switch 2 open while the switch I isopened by the spring 5. At the same time, engagement of the switch bladeIII with the contact I25 establishes a circuit for energizing the valveoperating coil 63 to effect closing of the disconnecting switch 3. Thiscircuit may be traced from the conductor 11 through the conductors 19,and IOI, the switch blade III, contact I25, a conductor I55, coil 63,conductor I45, auxiliary contacts I41, conductor I49, auxiliary contacts|5| which close when the interrupting switch I reaches open position,conductors 9| and 93 to the conductor 95. Operation of the valve 59 bythe coil 63 admits compressed air to the right of the piston 53, whichnow occupies a position in the right-hand end of the cylinder 5|, toeiTect closing of the switch 3. The manual switch I05 may now bereleased. As the switch I05 moves to its neutral position, the coil I29of the lockout relay I21 is deenergized, since the contacts I53 openedwhen the switch 3 closed, permitting the switch 2 to go to its closedposition. The interrupting switch I may now be closed and the reclosingswitch reset to its open position in the previously described manner bydepressing the switch member 91 to close contacts 91 which energize thevalve operating magnet 43.

It will be seen from the foregoing description that the circuit isalways caused to be open at the switches and 2 whenever thedisconnecting switch is operated either to closed or to open position.

Auxiliary compression chambers I51 and I59 are provided in the cylinder5| communicating with the cylinder on both sides of the piston 53 toprovide a sufiicient supply of air under pressure to insure completeopening and closing movements of the disconnecting switch 3 in the eventthe switch I05 is released prematurely.

What is claimed is:

1. A circuit breaker comprising a circuit interrupting switch biasedopen, a circuit reclosing switch biased closed and connected in thecircuit of the breaker in parallel with said interrupting switch, meansfor releasably holding the interrupting switch closed and for holdingthe reclosing switch open, a disconnecting switch connected in thecircuit in series with the interrupting switch and the reclosing switch,operating means for opening and closing the disconnecting switch, andcontrol means operable to cause said operating means to open or to closethe disconnecting switch and to cause the interrupting switch and thereclosing switch to be open during operation of the disconnectingswitch.

2. A circuit breaker comprising a circuit interrupting switch biasedopen, a circuit reclosing switch biased closed and connected in thecircuit controlled by the breaker in parallel with said interruptingswitch, means for releasably hold-- ing the interrupting switch closedand for holding the reclosing switch open, additional means for holdingthe reclosing switch open, a disconnecting switch connected in thecircuit in series relation with the interrupting switch and thereclosing switch, operating means for said disconnecting switch, andcontrol means operable to cause release of the interrupting switch andthe additional holding means to hold the reclosing switch open and forcausing the operating means to open the disconnecting switch after theinterrupting switch reaches open position.

3. A circuit breaker comprising a circuit interrupting switch biasedopen, a circuit reclosing switch biased closed and connected in thecircuit in parallel with said interrupting switch, means for releasablyholding the interrupting switch closed and for holding the reclosingswitch open, additional means for holding the reclosing switch open, adisconnecting switch connected in the circuit in series relation withthe interrupting switch and with the reclosing switch, operating meansfor opening and closing said disconnecting switch, and control means forsaid circuit breaker for initiating an opening movement of theinterrupting switch, for causing the additional holding means tomomentarily hold the reclosing switch open when the inter-- ruptingswitch opens and for causing an opening movement of the disconnectingswitch in the time interval during which both the interrupting switchand the reclosing switch are open.

4. A circuit breaker comprising a circuit interrupting switch biasedopen, a circuit reclosing switch biased closed and connected in thecircuit in parallel relation with said interrupting switch, means forreleasably holding the interrupting switch in closed position and forholding the reclosing switch in open position, a disconnecting switchconnected in the circuit in series relation with the interrupting switchand the reclosing switch, operating mechanism for opening and closingsaid disconnecting switch, control means operable to cause release ofthe interrupting switch and to cause the operating mechanism to open thedisconnecting switch after the interrupting switch reaches openposition, and means controlled by the reclosing switch to preventopening of the disconnecting switch while said reclosing switch is inclosed position.

5. A circuit breaker comprising a circuit interrupting switch biased inopening direction, a circuit reclosing switch biased in closingdirection and connected in the circuit controlled by the breaker inparallel relation with said interrupting switch, means for releasablyholding the interrupting switch closed and for holding the reclosingswitch open, a disconnecting switch connected in the circuit in seriesrelation with said interrupting switch and said reclosing switch, acompressed air operating mechanism [or opening and closing thedisconnecting switch, control means including a manually operablecontroll r operable to cause an opening operation of the interruptingswitch and to cause opening of the disconnecting switch after theinterrupting switch reaches open position,

means comprising an air reservoir to insure a complete opening operationof the disconnecting switch in the event of premature return of thecontroller to inoperative position, and means controlled by thereclosing switch to prevent opening of said disconnecting switch whilesaid reclosing switch is in closed position.

6. A circuit breaker comprising a circuit interrupting switch biased inan opening direction, a circuit reclosing switch biased in a closingdirection and connected in the circuit in shunt relation to saidinterrupting switch, means for releasably holding the interruptingswitch closed and for holding the reclosing switch open, a disconnectingswitch connected in the circuit in series relation with the interruptingswitch and the reclosing switch, a compressed air operating mechanismfor opening and closing said disconnecting switch, control means forsimultaneously initiating an opening movement of the interrupting switchand an operation of the operating mechanism to open the disconnectingswitch, means operated by the interrupting switch to prevent operationof the operating mechanism until the interrupting switch is open, andmeans controlled by the reclosing switch to prevent opening of saiddisconnecting switch while said reclosing switch is in closed position.

7. A circuit breaker comprising a circuit interrupting switch biased inopening direction, a normally open circuit reclosing switch biased inclosing direction and connected in the circuit in parallel with saidinterrupting switch, means for releasably restraining the interruptingswitch in closed position and the reclosing switch open, a disconnectingswitch connected in the circuit in series relation with the interruptingswitch and the reclosing switch, additional restraining means forholding the reclosing switch in open position, operating mechanism foropening and closing said disconnecting switch, control means forsimultaneously causing operation of the restraining means to release theinterrupting switch, for initiating an opening operation of theoperating mechanism, and for rendering the additional restraining meanseffective to restrain the reclosing switch in open position, meanscontrolled by the interrupting switch to prevent opening of thedisconnecting switch until said interrupting switch is opened, and meanscontrolled by the reclosing switch to prevent operation of the operatingmechanism when said reclosing switch is closed.

8. A circuit breaker comprising circuit interrupting contacts biased inan opening direction, circuit reclosing contacts biased in a closingdirection and connected in the circuit in parallel relation with saidinterrupting contacts, means for releasably restraining the interruptingcontacts in closed position and for restraining said reclosing contactsin open position, additional restraining means eperable at times forrestraining the reclosing contacts in open position, disconnectincontacts connected in the circuit in series relation with theinterrupting contacts and the reclosing contacts, operating means foropening and closing said disconnecting contacts, operating means forclosing the interrupting contacts and for opening the reclosingcontacts, control means for initiating an opening movement of theinterrupting contacts, for causing an operation of the additionalrestraining means to hold the reclosing contacts in open position, andfor causing operation of the disconnecting contacts after theinterrupting switch reaches open position, and means to preventoperation of said disconnecting contacts except when the interruptingcontacts and the reclosing contacts are in open position.

9. A circuit breaker comprising circuit interrupting contacts, circuitreclosing contacts connected in the circuit in parallel relation withsaid interrupting contacts, means for releasably holding theinterrupting contacts in closed position and for holding said reclosingcontacts in open position, disconnecting contacts connected in thecircuit in series relation with the interrupting contacts and thereclosing contacts, operating mechanism for opening and closing saiddisconnecting contacts, means for causing opening of the interruptingcontacts and closing of the reclosing contacts, and control means forcausing an operation of the operating means for the disconnectingcontacts only after the interrupting contacts are open and before thereclosing contacts close.

10. A circuit breaker comprising circuit interrupting contacts biasedopen, circuit reclosing contacts biased closed and connected in thecircuit in parallel relation with the interrupting contacts, means forreleasably holding the interrupting contacts closed and the reclosingcontacts open, disconnecting contacts connected in the circuit in seriesrelation with the interrupting contacts and the reclosing contacts,operating means for opening and closing the disconnecting contacts,means for causing opening of the interruptlng contacts and closing ofthe reclosing contacts, and control means for causing the operatingmeans to close the disconnecting contacts only after the interruptingcontacts are open and before the reclosing contacts close.

11. A circuit breaker comprising a circuit interrupting switch biasedopen, a circuit reclosing switch biased closed and connected in parallelwith the interrupting switch in the circuit, means for releasablyholding th interrupting switch closed and the reclosing switch open,trip means operable when energized to release said switches, holdingmeans including an electromagnet operable when energized to hold thereclosing switch open, a disconnecting switch connected in the circuitin series relation with the interrupting switch and the reclosingswitch, operating mechanism for opening and closing said disconnectingswitch, a control circuit for simultaneously energizing the trip meansto effect opening of the interrupting switch, energizing the holdingmeans to prevent closing of the reclosing switch,

and for causing operation of the operating mechanism to efiect openingor closing of the disconnecting switch, after the interrupting switchreaches open position, and means to prevent closing of the reclosingswitch until the disconnecting switch is fully opened or closed.

12. A circuit breaker comprising a circuit interrupting switch biasedopen, a circuit reclosing switch biased closed and connected in thecircuit in parallel with the circuit interrupting witch, means foreffecting opening and closing of said switches, a disconnecting switch,operating mechanism for opening and closing said disconnecting switch,means comprising a plurality of electromagnets operable when energizedto cause the operating mechanism to operate the disconnecting switch toits open or closed positions, and means to prevent energization of saidelectromagnets when either the interrupting switch or the reclosingswitch is closed.

13. Electrical circuit controlling apparatus movable to a secondposition to cause the intercomprising a circuit interrupter operable toopen and automatically reclose the circuit, a disconnecting switchconnected in the circuit in series with the circuit interrupter, meansoperable in response to predetermined abnormal conditions in the circuitto cause said circuit interrupter to open and automatically reclose thecircuit, said disconnecting switch remaining closed during operation ofsaid interrupter in response to said abnormal conditions, and controlmeans operable at will to cause opening or closing of said disconnectingswitch and to cause said interrupter to open the circuit prior toopening or closing of the disconnecting switch and to maintain thecircuit open during operation of said disconnecting switch. v

14. Electrical circuit controlling apparatus comprising a circuitinterrupting device operable to open and automatically reclose thecircuit, operating means for said circuit interrupting device, meansoperable in response to predetermined abnormal conditions in the circuitto cause operation of said circuit interrupting device to open andautomatically reclose the circuit, a disconnecting switch connected inseries with said circuit interrupting device, operating means for saidswitch, and control means for the operating means of said interruptingdevice and switch operable at will to cause said circuit interruptingmeans to interrupt the circuit and then cause opening or closing of saiddisconnecting switch and to maintain said circuit interrupting means inopen position at least until operation of said switch has beencompleted.

15. Electrical circuit controlling apparatus comprising a circuitinterrupter operable to open and automatically reclose the circuit,operating means for said circuit interrupter, means operable in responseto predetermined abnormal conditions in the circuit to cause operationof the interrupter to open and automatically reclose the circuit, adisconnecting switch in series with said interrupter, operating meansfor said switch, and control means for jointly controlling the operatingmeans of said interrupter and switch, said control means including amanually operable controller operable to cause said interrupter to openand be maintained open as long as said controller is held in operatedposition and for causing opening or closing of said switch after saidinterrupter reaches open position.

16. Electrical circuit controlling apparatus comprising a circuitinterrupter operable to open and automatically reclose the circuit,operating means for said circuit interrupter, means operable in responseto predetermined abnormal conditions in the circuit to cause operationof the interrupter to open and automatically reclose the circuit, adisconnecting switch in series with said interrupter, operating meansfor said switch, and control means for jointly controlling the operatingmeans of said interrupter and switch, said control means including amanually operable controller movable to one position to cause theinterrupter to open and then the switch to open and rupter to open andthen the switch to close, said control means causing the interrupter toremain in open position until the operation of said switch has beencompleted.

17. Electrical circuit controlling apparatus comprising a circuitinterrupter operable to open and automatically reclose the circuit,operating means for said circuit interrupter, means operable in responseto predetermined abnormal conditions in the circuit to cause operationof the interrupter to open and automatically reclose the circuit, adisconnecting switch in series with said interrupter, operating meansfor said switch, and control means for jointly controlling the operatingmeans of said interrupter and switch, said control means including amanually operable controller movable to one position to cause theinterrupter to open and then the switch to open and movable to a secondposition to cause the interrupter to open and then the switch to close,said control means maintaining said interrupter in open position as longas said controller is held in either of said positions.

18. Electrical circuit controlling apparatus comprising circuitinterrupting means operable in response to predetermined abnormalconditions in the circuit to open and automatically reclose the circuit,operating means for the circuit interrupting means, a disconnectingswitch connected in the circuit in series with the circuitinterruptingmeans, operating means for said switch, and control means for jointlycontrolling the operating means of the circuit interrupting means andswitch, said control means being operable to cause the circuitinterrupting means to interrupt the circuit and maintain the circuittemporarily interrupted and to open or close the disconnecting switchduring the interval when the circuit is temporarily interrupted at thecircuit interrupting means.

19. Electrical circuit controlling apparatus comprising a circuitinterrupter havinga pair of circuit interrupting contacts and a secondpair of contacts in parallel therewith for reclosing the circuit,operating means for the interrupter operable in response topredetermined abnormal conditions in the circuit to cause the circuitinterrupter to open the circuit by the interrupting contacts andautomatically reclose the circuit by said second pair of contacts, adisconnecting switch connected in the circuit in series with the circuitinterrupter, operating means for said switch, and control means forjointly controlling the operating means of the interrupter and switch,said control means being operable to cause opening of said circuitinterrupting contacts and opening or closing of said switch after theinterrupting contacts reach open position and for maintaining saidsecond pair of contacts of the interrupter temporarily open until theoperation of said switch is completed.

WERNER KAUFMAN N.

